For coupling and providing a battery stack a battery module and a method for its production are known from DE 10 2007 046 043 A1, which is incorporated herein by reference. Such a battery module represents a battery cell stack and couples a first and a second battery cell to each other via a connecting element from a metal sheet. This connecting element according to the state of the art is formed from a tube and has a bottom part and a side wall. The bottom part in turn has an outer edge element, which is welded to a bottom wall of the battery cell housing of the second stacked battery cell, while an inner edge element is welded within the outer edge element to a locking plate of the first battery cell. Such a battery stack of two battery cells stacked one onto the other results in a battery module, which consists of stacked batteries which are connected in series, whereby the voltage is doubled and the storage capacity corresponds to an individual battery cell.
A disadvantage of this battery stack is that it is not possible to increase the storage capacity by parallel connection of the stacked battery cells via the disclosed connecting element.
From U.S. 2002/0064708 A1, which is incorporated herein by reference, a battery module made of prismatic battery cells is known, which has also a plurality of prismatic battery cells connected in series, wherein positive and negative electrical tags are alternately stacked via a separator and flat conductor connections are connected to each other on opposite sides by protruding portions of the positive and negative electrical tags. Here, bus bars on the flat conductor sections on both sides of the electrode tags are connected to groups while using an electrically conductive adhesive or the like. These groups of electrode tags are in turn serially connected to each other and then the spaces between the bus bars and the battery wall are molded with a non-conductive material to isolate the many battery cells from each other. Here, a construction is achieved, which in fact makes it possible to shorten the electrical connecting paths and thus to decrease the internal resistance, however, with this connection technology merely the total voltage of the battery can be increased, however, not the ability to receive and deliver current, i.e. the capacity of the battery cannot be improved.